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a-camp
12-17-2004, 09:26 AM
My front end is mush on my 86 250r. I was going to purchase a set of Progessive springs next year. 3rd on list. My friends tell me to drop short cuts of PVC in tubes for now to use as bushings. Could this work ? Or will they split?

TrikerR
12-17-2004, 11:07 AM
they should hold for a while, definately long enough to get some better springs

smokinwrench
12-18-2004, 11:13 AM
I done the pvc pipe trick to my 250r. I took a fork cap with me to the hardware store so I could get the biggest diameter size possible. I bought couplers since they are thicker then just pipe. I cut each 1 to 1 inch long. It was the best, cheapest upgrade I ever done to my 250r. I would have put longer pieces in but couldn't get them shoved in without lots of trouble and probably a black finger nail.

Blown 331
12-18-2004, 11:23 AM
What exaclty are you guys talking about?

a-camp
12-18-2004, 11:32 AM
Front spings on my bike are mush . My bike sits low in the front.I headr if you put s
small pieces of PVC in your fork it will compress the spings and lift you up.
Thanks for the replie.

TimSr
12-18-2004, 01:28 PM
Its called preload, and it does the same thing as adjusting the large nut on the rear shock. When you buy progressive springs from Dennis Kirk they are packaged with two standard PVC pipe pieces a few inches long that you can cut to desired length or leave out altogether.

Dynofox
12-18-2004, 02:39 PM
I did that trick to both my tri z and 350x since those trikes have soft front suspensions. What shape are your fork seals in (do they leak)?

a-camp
12-18-2004, 08:19 PM
My seals are new . Been trying different oil levels and weight. Im at 450cc per ? Is this good. Anyone know what weight on oil.

a-camp
12-23-2004, 10:20 AM
I did it . I used a 1inch sch80 nipple . I found one with no seams and cut two 1 1/2 inch pieces out of the center. It lifted the front of my bike nice . We will see what happens when I jump.

Jeb
12-23-2004, 11:02 AM
The PVC should be fine from now on, but if your that worried about it use aluminum tubing for your pre-load spacers. :beer

sandrooster
12-23-2004, 11:21 AM
... Anyone know what weight on oil.

The sag is from worn out springs.

I use Belray 10wt fork oil in one of my 85Rs. It seems to work the best for all around riding.
In the other 85R, I tried 5 than the 7 weight fork oils because I ride alot of high speed washboards. On the washboards at speed, the lighter oil gives the forks the feeling of quicker response. But I really don't like to get serious air on this one cause the forks bottom. This is with no air pressure.

So 10wt to start is my recommendation.

TimSr
12-23-2004, 10:58 PM
The sag is from worn out springs.

I use Belray 10wt fork oil in one of my 85Rs. It seems to work the best for all around riding.
In the other 85R, I tried 5 than the 7 weight fork oils because I ride alot of high speed washboards. On the washboards at speed, the lighter oil gives the forks the feeling of quicker response. But I really don't like to get serious air on this one cause the forks bottom. This is with no air pressure.

So 10wt to start is my recommendation.

Its refreshing to see advice given by someone who understands suspension!

Oil, springs, and preload, optimum is as light as you can possibly go without frequently bottoming out.

Preloading worn out springs to eliminate sag is a bandaid, not a performance modification. Preloading progressive springs is for the purpose of selecting the begining spring weight for your compression range. Use as little as necessary, none of possible.

Heavy oil retards fork reaction. It does not make them stiffer, but it will sure make them ride rougher. Go as light as possible. Use the MFG recommended amount. Your not going to gain anything by adding more, and if you add too much, it will blow out your seals, because oil cannot compress. You can only loose some of your dampened range of extension by running less.

Air pressure should be at 0. Adding a little air can help compensate for weak springs, but its a crappy substitute for proper spring length, and stiffness. It too is a bandaid, and not a performance modification.

a-camp
12-23-2004, 11:13 PM
Sounds good I am running 10 w after trying several different weights . I also am back to 450cc per as you saggested. I found with to much it feels like your bottoming out if your seals hold. Thanks for good input.